A HISTORY OF SURREY 



pasture land from a hilltop would produce ' shrimps,' or any other 

 aquatic organisms, was an expectation that required some robustness of 

 faith even in the zoologists of the party. If it inspired others with 

 incredulous amusement they could scarcely be blamed. On August 21 

 some of the earth was placed in water. On the thirtieth it proved to 

 have Ostrac6da alive in it and a Chirocephalus a quarter of an inch 

 long. The next day a second Chirocephalus was perceived of slightly 

 smaller size. Both of these must have been born some days earlier. 

 On September 6 the rest of the earth was put into water, and on the 

 eleventh minute animals were found to be moving about, two of which 

 appeared on the following day to be microscopic Chirocephali. It was 

 pleasant to watch these creatures, and the preliminary to watching them 

 was itself interesting. So artfully are they adapted chameleon-like to 

 their surroundings, that even when full-grown in a small bowl under a 

 good reading-glass they are not at once discoverable. When found 

 they are seen sometimes to make rapid darts and sudden evolutions, more 

 often to glide serenely along, or at will simply to hover in the water, 

 with their eleven pairs of leaf-like limbs all the while in constant motion. 

 The development of the sexual distinctions is also of interest. In the 

 male the prehensile second antennas and the digitate frontal processes 

 are highly characteristic. The full-grown female is quite as easily dis- 

 tinguishable by her long projecting marsupium. In this, at least while 

 not filled with eggs, the glandular structure which supplies the egg- 

 shells appears to be in ceaseless activity. Difficult as it is to discriminate 

 the animal from the mud over which it is swimming, it is far from being 

 mud-coloured. It has a general tint of transparent greenish-brown, 

 with blue on the back along the region of the heart ; the large lateral 

 eyes show red under a favourable light ; the small median eye-spot is 

 dark, the marsupial gland brown, the caudal furca bright red. The 

 back is almost always downwards. The colours vanish in spirit, except 

 that the marsupial gland retains some of its brown hue, and the eyes 

 appear as black under a white coating. In the chilly part of the autumn 

 the specimens which had not been put into spirit buried themselves 

 in the earth, and have not reappeared. Whether under any circum- 

 stances they would have done so I cannot say for certain. It was 

 eminently improbable that they would do so under the conditions they 

 actually experienced, for during the winter the water was allowed to 

 evaporate without being replenished, and the earth became by degrees 

 a hard mass in the bowls. On April 9, 1901, water was again poured 

 upon it, with the result that on the twentieth of the month a Chiro- 

 cephalus about a tenth of an inch long was descried, and soon afterwards 

 a second made its appearance. At the time of writing, May 10, the 

 specimens are swimming about in a lively manner, one of them showing 

 the characters of a female. Scores of Ostracoda are displaying an even 

 greater vivacity, and if so much energy cannot be sustained without 

 animal food, it is perhaps these minute creatures which keep down the 

 phyllopod population by massacring their defenceless young. The 



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